Acoustica Mixcraft 7 - Manual (Page 183)

177
Should I change the default frame rate?
Probably not. Increasing the frame rate to one higher than any of the project’s video
clips won’t improve final video quality, while decreasing the frame rate will usually
lower the quality. Even if the primary concern is video size, changing the frame rate
is not necessarily useful; depending on the chosen encoding method, lowering the
frame rate can potentially increase the file size. If you’re trying to alter the frame rate to
produce smaller file sizes, you’ll need to experiment to find the best setting.
VIDEO ENCODING
This setting specifies approximately how much bandwidth video playback will require,
in kilobits per second. It’s one of the primary factors affecting compression. A higher bit
rates mean larger files and higher quality, while lower bit rates result in smaller, lower
quality video files. The right bit rate to use will depend on the dimensions and frame
rate. A bit rate that produces a high quality 720 x 480 video may result in a grainy,
pixelated video at 1440 x 1080. Again, you’ll likely need to experiment for best results.
Microsoft provides a handful of encoding methods for WMV creation. Which one to
use depends on your priorities (quality vs. file size) as well as the video content. In
practice, an encoding method that produces the best results for one video may not
produce the best results for another.
 Constant Bit Rate (One Pass)
This method was designed to handle live streaming video and will usually
produce the lowest quality results when rendering to a file. Because it’s a one-
pass method, though, it takes half as long to render to file as the two-pass
methods, so it might be the choice for you if the world’s ending in a few
minutes and you really want to be able to watch the video before it’s all over.
 Constant Bit Rate (Two Pass)
This method will usually produce good quality video if you’ve set a
sufficiently high bit rate. Because it’s a two-pass method, it’ll take twice as
long to create the video as one-pass methods will. Since the bit rate will be
consistent for the entire video, it should work well for videos intended to
stream over a network or the internet.
 Variable Bit Rate with Quality Setting
Using this encoding method with the quality slider at its highest setting
usually results in higher quality videos than the aforementioned encoding
methods. However, the resulting video files tend to be about three times
larger. Use this method if quality is the highest priority. This is a one-pass
encoding method, which means it will take roughly half as long to create
the video as with two-pass methods. (The number of passes refers only to the
creation of the video, and doesn’t affect the speed of video playback.)